Validity Test for a Set of Nonlinear Measures for Short Data Length with Reference to Short-Term Heart Rate Variability Signal. - Remzi Seker; Sokol Saliu; Ahmet Birand; Gulmira Kudaiberdieva (J. Syst. Integr., 2000)

Bispectral analysis of heart rate variability signal. - Sokol Saliu; Ahmet Birand; Gulmira Kudaiberdieva (EUSIPCO, 2002)